Note: Descriptions are shown in the official language in which they were submitted.
1.
METHOD AND APPARATUS FOR SETTING DOWNHOLE PLUGS AND OTHER
OBJECTS IN WELLBORES
BACKGROUND OF THE INVENTION
1. Field of the Invention
[0001] The present invention pertains to a setting tool that can be
used to set plugs
and other downhole equipment within wellbores. More particularly, the present
invention pertains to a compact and cost-efficient setting tool that can be
conveyed via
wireline for setting downhole tools and other equipment with wellbores.
2. Brief Description of the Prior Art
[0002] Wells are typically drilled into the earth's crust using a
drilling rig or other
similar equipment. After a section of wellbore has been drilled to a desired
depth, a
string of pipe known as casing is typically conveyed into said well and
cemented in
place. The casing is often installed to provide structural integrity to the
wellbore and
to keep geologic formations isolated from one another.
[0003] In some applications, a wireline tool string may be run into
the wellbore after
the casing has been installed in a well. Although many different
configurations are
possible, the wireline tool string may include a downhole plug that may be set
within
the inner bore of the casing string at a desired location in the wellbore, as
well as a
setting tool for setting said downhole plug. Generally, such a plug is used to
isolate
one portion of a wellbore from another. Although this operation is commonly
used in
1
CA 3081120 2020-05-14
., ..
many different operations, such wellbore plugs are commonly used in connection
with
hydraulic fracturing operations.
[0004] Conventional downhole wireline setting tools (for example, a
"Baker 20") are
long, complex, and require multiple personnel to handle. Thus, it would be
beneficial
to have a downhole wireline setting tool that is shorter and lighter than
conventional
setting tools. Further, the setting tool should beneficially have less
components, be
capable of being redressed and reused more quickly, and be easier to operate
than
conventional wireline setting tools.
SUMMARY OF THE INVENTION
[0005] The present invention comprises a wireline conveyed, gas
driven setting tool
designed to set downhole tools, such as fracturing ("frac") plugs, zone
isolation plugs,
bridge plugs, cement retainers, and packers. The setting tool of the present
invention
is functioned by igniting a power charge inside a firing head. As said power
charge
burns, the combustion generates gas that acts upon a piston area to stroke
setting
components of the apparatus.
[0006] The setting tool of the present invention generally comprises
pressure sub,
upper sleeve member, lower sleeve member, central tension mandrel, and tension
mandrel adapter. In a preferred embodiment, the central longitudinal axes of
each of
said pressure sub, upper sleeve member, lower sleeve member and central
tension
mandrel are all oriented substantially parallel to each other. The lower
sleeve member
2
CA 3081120 2020-05-14
.. .,
is secured to upper sleeve member which, in turn, is secured against movement
along
the length of central tension mandrel using at least one shear screw (or pin).
[0007]
The setting tool is functioned by selectively igniting a power charge
inside of
a pressure chamber formed within said pressure sub. As the power charge burns,
it
generates gas that acts upon a piston area to shear said shear screw(s) and
stroke
the setting tool. A dampening media, as well an optimized flow area at or near
the
distal end of the setting tool, act to slow or regulate the setting stroke.
When stroked,
said upper sleeve member and lower sleeve member are displaced along the
longitudinal axis of said tension mandrel, thereby causing an attached
downhole plug
or other object to be set according to a process understood by those in the
art that, for
clarity and conciseness, is not described in detail in this disclosure.
[0008]
The setting tool of the present invention is shorter and lighter than
conventional setting tools. Further, the setting tool of the present invention
has less
components, can be redressed in a fraction of the time compared to
conventional
setting tools, and can be efficiently operated by a single person.
Unlike many
conventional setting tools, the setting tool of the present invention does not
require oil
to dampen setting force. As a result, the setting tool of the present
invention requires
less parts and seal areas (potential leak paths), while eliminating risk for
human error
(that is, forgetting the oil entirely or loading the incorrect volume of oil).
[0009]
The setting tool of the present invention utilizes a dampening assembly
within said setting tool to slow the setting stroke of the tool; such
dampening effect is
frequently beneficial when setting tools and other equipment downhole within a
3
CA 3081120 2020-05-14
.. ..
wellbore. Additionally, an optimized flow area at or near the bottom or distal
end of the
setting tool also acts to slow said setting stroke.
BRIEF DESCRIPTION OF DRAWINGS/FIGURES
[0010] The foregoing summary, as well as any detailed description of
the preferred
embodiments, is better understood when read in conjunction with the drawings
and
figures contained herein. For the purpose of illustrating the invention, the
drawings and
figures show certain preferred embodiments. It is understood, however, that
the
invention is not limited to the specific methods and devices disclosed in such
drawings
or figures.
[0011] FIG. 1 depicts a side perspective view of the setting tool
apparatus of the
present invention in a retracted or "un-stroked" configuration.
[0012] FIG. 2 depicts a side perspective view of the setting tool
apparatus of the
present invention in an extended or "stroked" configuration.
[0013] FIG. 3 depicts a side perspective and exploded view of the
setting tool
apparatus of the present invention.
[0014] FIG. 4 depicts a side view of the setting tool apparatus of
the present
invention in a retracted or "un-stroked" configuration.
[0015] FIG. 5 depicts a side view of the setting tool apparatus of
the present
invention in an extended or "stroked" configuration.
[0016] FIG. 6A depicts a first portion of the setting tool apparatus
of the present
invention along line 6-6 of FIG. 4.
4
CA 3081120 2020-05-14
.. ..
[0017] FIG. 6B depicts a second portion of the setting tool apparatus
of the present
invention along line 6-6 of FIG. 4.
[0018] FIG. 7A depicts a first portion of the setting tool apparatus
of the present
invention along line 7-7 of FIG. 5.
[0019] FIG. 7B depicts a second portion of the setting tool apparatus
of the present
invention along line 7-7 of FIG. 5.
[0020] FIG. 8 depicts a detailed view of the highlighted area
depicted in FIG. 6B.
[0021] FIG. 9 depicts a detailed view of the highlighted area
depicted in FIG. 7A.
[0022] FIG. 10 depicts a detailed view of the highlighted area
depicted in FIG. 7B.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION
[0023] While the present invention will be described with reference
to preferred
embodiments, it will be understood by those skilled in the art that various
changes may
be made and equivalents may be substituted for elements thereof without
departing
from the scope of the present invention. In addition, many modifications may
be made
to adapt a particular situation or material to the teachings of the invention
without
departing from the essential scope thereof. Therefore, it is intended that the
present
invention not be limited to the particular embodiments disclosed as the best
mode
contemplated for carrying out this invention, but that the invention will
include all
embodiments (and legal equivalents thereof).
[0024] Moreover, it will be understood that various directions such
as "upper",
"lower", "bottom", "top", "left", "right", and so forth are made only with
respect to
CA 3081120 2020-05-14
.. õ
explanation in conjunction with the drawings, and that components may be
oriented
differently, for instance, during transportation and manufacturing as well as
operation.
Because many varying and different embodiments may be made within the scope of
the concept(s) herein taught, and because many modifications may be made in
the
embodiments described herein, it is to be understood that the details herein
are to be
interpreted as illustrative and non-limiting. As used herein, the term "sub"
is intended
to generically refer to a section or a portion of a tool string. While a sub
may be modular
and use threaded connections, no particular configuration is intended or
implied by the
use of the term sub.
[0025]
FIG. 1 depicts a side perspective view of setting tool apparatus 100 of
the
present invention in a retracted or "un-stroked" configuration. As depicted in
FIG. 1,
said setting tool apparatus 100 generally comprises pressure sub 10, upper
sleeve
member 30, lower sleeve member 40, central tension mandrel 70 and tension
mandrel
adapter 90. In a preferred embodiment, the central longitudinal axes of each
of said
pressure sub 10, upper sleeve member 30, lower sleeve member 40 and central
tension mandrel 70 are all oriented substantially parallel to each other.
In the
configuration depicted in FIG. 1, lower sleeve member 40 is secured to upper
sleeve
member 30 which, in turn, is secured against movement along the length of
central
tension mandrel 70 using at least one shear screw (or pin) 25.
[0026]
FIG. 2 depicts a side perspective view of setting tool apparatus 100 of
the
present invention in an extended or "stroked" configuration. As depicted in
FIG. 2, said
at least one shear screw 25 has been sheared. As a result, upper sleeve member
30
6
CA 3081120 2020-05-14
.. ..
and attached lower sleeve member 40 are capable of movement along the length
of
central tension mandrel 70. In the configuration depicted in FIG. 2, said
upper sleeve
member 30 and lower sleeve member 40 are displaced along the longitudinal axis
of
said tension mandrel 70, thereby exposing at least a portion of body section
13 of
pressure sub 10.
[0027]
FIG. 3 depicts a side perspective and exploded view of setting tool
apparatus
100 of the present invention. Setting tool apparatus 100 generally comprises
pressure
sub 10, upper sleeve member 30, lower sleeve member 40, central tension
mandrel
70 and tension mandrel adapter 90.
In a preferred embodiment, the central
longitudinal axes of each of said pressure sub 10, upper sleeve member 30,
lower
sleeve member 40, central tension mandrel 70 and tension mandrel adapter 90
are all
oriented substantially parallel to each other.
[0028]
Pressure sub 10 generally comprises upper connection member 11 and
body section 13. In a preferred embodiment, said upper threaded connection
member
11 comprises a female or "box-end" threaded connection having internal threads
(not
visible in FIG. 3) that is configured for operational attachment to a
conventional wireline
or other connection adapter. However, it is to be observed that other types of
connection members having different thread types or other connection means can
be
employed without departing from the scope of the present invention. By way of
illustration, but not limitation, a pin-end threaded connection or other
attachment
means can be employed.
7
CA 3081120 2020-05-14
[0029] As depicted in FIG. 3, pressure sub 10 further comprises body
section 13
defining outer surface 15. Central through bore 18 extends through said
pressure sub
10. Lower connection threads 16 are disposed near the lower or distal end of
body
section 13; in the embodiment depicted in FIG. 3, said lower connection
threads 16
comprise internal threads disposed on the inner surface of central through
bore 18. At
least one circumferential groove 19 extends around body section 13 and is
configured
to receive elastomeric sealing elements, such as 0-rings 60. Further, radial
extension
ring 17 extends at least partially around the circumference of, and has a
greater outer
diameter than, said body section 13.
[0030] Central tension mandrel 70 comprises an elongate and substantially
rigid
member having a first end 78, second end 79 and body section 71 there between.
In
a preferred embodiment, said body section 71 has a substantially cylindrical
shape
defining outer surface 76. Lower threads 75 are disposed near second end 79;
in the
embodiment depicted in FIG. 3, said threads 75 comprise external threads. At
least
one circumferential step-down or change in outer diameter 76 extends around
body
section 71 near the lower or distal end of said central mandrel 70.
[0031] Central tension mandrel 70 further comprises connection member 72
disposed at or near first end 78 of said central tension mandrel 70. In a
preferred
embodiment, said connection member 72 has external male threads 73 configured
to
mate with internal threads 16 of pressure sub 10. Further, at least one
elongate flow
path 74 (such as a groove or channel) extends through said threads 73. In a
preferred
embodiment, said at least one flow path 74 comprises a channel oriented
substantially
8
CA 3081120 2020-05-14
.. .,
parallel to the longitudinal axis of body section 71 and substantially
perpendicular to
the direction or orientation of said threads 73; however, it is to be observed
that said
at least flow path can have a different orientation without departing from the
scope of
the present invention, so long as it permits flow of fluid past said
connection member
72. Internal plug 50 having an aperture 51 (not visible in FIG. 3) is
operationally
attached to connection member 72. Ball 29 is disposed within said internal
plug 50
and is configured to selectively block said aperture 51 as more fully
described herein.
[0032]
Upper sleeve member 30 generally comprises a cylindrical member having
a through bore 31 extending substantially along the longitudinal axis of said
upper
sleeve member 30.
Similarly, lower sleeve member 40 comprises a cylindrical
member having a through bore 41 extending substantially along the longitudinal
axis
of said lower sleeve member 40. At least one transverse side port 44 extends
from
said through bore 41 to the external surface of said lower sleeve member 40.
Lower
threads 42 are disposed at or near the lower or distal end of lower sleeve
member 40.
[0033]
Lower threads 32 are disposed at or near the lower or distal end of said
upper sleeve member 30; in a preferred embodiment, said threads 32 are
configured
to engage with mating threads disposed on the inner surface of central through
bore
41 of lower sleeve member 40 (not visible in FIG. 3). In a preferred
embodiment, the
central longitudinal axes of each of said pressure sub 10, upper sleeve member
30,
lower sleeve member 40, central tension mandrel 70 and tension mandrel adapter
90
are all oriented substantially parallel to each other.
9
CA 3081120 2020-05-14
.. . ,
[0034] Cushion member 91 is received on tension mandrel 70. In a
preferred
embodiment, said cushion member 91 comprises a resilient or padded material
(such
as an elastomeric or foam material) configured to lessen or dampen force
exerted
between members contacting each other. Tension mandrel adapter member 90 is
secured at second end 79 of tension mandrel 70 using lower threads 75.
[0035] FIG. 4 depicts a side view of setting tool apparatus 100 of
the present
invention in a retracted or "un-stroked" configuration. As depicted in FIG. 4,
said setting
tool apparatus 100 generally comprises pressure sub 10, upper sleeve member
30,
lower sleeve member 40, central tension mandrel 70 and tension mandrel adapter
90.
Tension mandrel adapter member 90 is secured near the lower or distal end
(second
end 79) of tension mandrel 70. Lower sleeve member 40 is secured to upper
sleeve
member 30 which, in turn, is secured against movement along the length of
central
tension mandrel 70 using at least one shear screw (or pin) 25.
[0036] FIG. 5 depicts a side view of setting tool apparatus 100 of
the present
invention in an extended or "stroked" configuration. As depicted in FIG. 5, at
least one
shear screw 25 is sheared or separated and, as such, is not constrained from
axial
movement by radial extension ring 17 that extends at least partially around
the
circumference of said body section 13. As a result, upper sleeve member 30 and
attached lower sleeve member 40 are capable of movement along the longitudinal
axis
or length of central tension mandrel 70.
[0037] Still referring to FIG. 5, said upper sleeve member 30 and
lower sleeve
member 40 are displaced along the longitudinal axis of said tension mandrel
70,
CA 3081120 2020-05-14
thereby exposing at least a portion of body section 13 of pressure sub 10. In
this
configuration, 0-rings 60 disposed around said body section 13 are no longer
positioned to engage against central bore 31 of upper sleeve member 30.
Further, in
the configuration depicted in FIG. 5, it is to be observed that lower threads
42 at the
distal end of lower sleeve member 40 extend beyond tension mandrel adapter 90
(visible in FIG. 4 but not FIG. 5).
[0038] FIG. 6A depicts a first (upper) portion of setting tool apparatus
100 of the
present invention along line 6-6 of FIG. 4, while FIG. 6B depicts a second
(lower)
portion of said setting tool apparatus 100 of the present invention along line
6-6 of FIG.
4. Setting tool apparatus 100 generally comprises pressure sub 10, upper
sleeve
member 30, lower sleeve member 40, central tension mandrel 70 and tension
mandrel
adapter 90.
[0039] Referring to FIG. 6A, pressure sub 10 generally comprises upper
connection
member 11 and body section 13. In a preferred embodiment, said upper threaded
connection member 11 comprises a female or "box-end" threaded connection
having
internal threads 12 that are configured for operational attachment to a
conventional
wireline or other connection adapter.
[0040] Still referring to FIG. 6A, pressure sub 10 further comprises body
section 13
defining outer surface 15. Central through bore 18 extends through said
pressure sub
10, while lower connection threads 16 are disposed near the lower or distal
end of body
section 13. Elastomeric sealing elements, such as 0-rings 60, are disposed
within
circumferential grooves extending around body section 13; said 0-rings 60
engage
11
CA 3081120 2020-05-14
against inner surface 31a of central bore 31 of upper sleeve member 30 in
order to
form a fluid pressure seal.
[0041] Further, radial extension ring 17 extends at least partially around
the outer
circumferential surface of said body section 13. At least one shear screw 25
is
disposed within a transverse bore extending through upper sleeve member 30 and
engages against a shoulder surface 17a of radial extension ring 17; in this
configuration, said at least one shear screw 25 prevents axial movement of
upper
sleeve member 30 (as well as any operationally attached components) along the
longitudinal axis of central tension mandrel 70.
[0042] Central tension mandrel 70 comprises an elongate and substantially
rigid
member having a first end 78, second end 79 and body section 71 defining outer
surface 76. Elastomeric sealing elements, such as 0-rings 61, are disposed
within
circumferential grooves extending around body section 71; said 0-rings 61
engage
against outer surface 76 of central mandrel 70 in order to form a fluid
pressure seal in
the un-stroked position. In a preferred embodiment, central bore 31 has a
smaller ID
in the vicinity of 0-rings 61 than near 0-rings 60.
[0043] Central tension mandrel 70 further comprises connection member 72
disposed at or near first end 78 of said central tension mandrel 70. In a
preferred
embodiment, said connection member 72 has external male threads 73 configured
to
mate with internal threads 16 of pressure sub 10. Although not visible in FIG.
6B, at
least one flow path 74 extends through said threads 73 and permits flow of
fluid past
connection member 72 as more fully described herein.
12
CA 3081120 2020-05-14
., ..
[0044] Internal plug or housing 50 having aperture 51 is
operationally attached to
connection member 72. Said internal plug 50 further defines an inner chamber
or void
52. Ball 29 is moveably disposed within said inner chamber or void 52 of said
internal
plug 50, and is configured to selectively seat against said internal plug 50
in order to
selectively block or obstruct said aperture 51.
[0045] Lower sleeve member 40 comprises a cylindrical member having a through
bore 41 extending substantially along the longitudinal axis of said lower
sleeve member
40. At least one transverse side port 44 extends from said through bore 41 to
the
external surface of said lower sleeve member 40, while threads 42 are disposed
at or
near the lower or distal end of lower sleeve member 40. Threads 32 of upper
sleeve
member 30 are configured to engage with mating threads 43 disposed on the
inner
surface of central through bore 41 of lower sleeve member 40. Cushion member
91 is
received on tension mandrel 70. Tension mandrel adapter member 90 is secured
at
second end 79 of tension mandrel 70 using lower threads 75.
[0046] FIG. 8 depicts a detailed view of the highlighted area
depicted in FIG. 6B.
Central bore 18 extends through said pressure sub 10, while lower connection
threads
16 are disposed near the lower or distal end of body section 13. Elastomeric
sealing
elements (0-rings) 60 engage against inner surface 31a of central bore 31 of
upper
sleeve member 30 in order to form a fluid pressure seal. Similarly,
elastomeric sealing
elements (0-rings 61) extend around body section 71 of tension mandrel 70;
said 0-
rings 61 engage against outer surface 76 of central mandrel 70 in order to
form a fluid
pressure seal in the un-stroked position.
13
CA 3081120 2020-05-14
[0047] Connection member 72 is disposed at or near first end 78 of said
central
tension mandrel 70. Although not visible in FIG. 8, at least one flow path 74
extends
through said threads 73 of connection member 72 and permits flow of fluid past
said
connection member 72 as more fully described herein. Internal plug 50 having
aperture 51 defines an inner chamber or void 52. Ball 29 is moveably disposed
within
said inner chamber or void 52 of said internal plug 50, and is configured to
selectively
seat against said internal plug 50 in order to selectively block or obstruct
aperture 51.
[0048] Setting tool 100 of the present invention maintains a fluid pressure
that is
supplied or energized by pressurized gas. Said fluid pressure is converted
into force
or kinetic energy used to displace a portion of said setting tool 100 that, in
turn, axially
displaces outer shifting sleeve component of a separate wellbore device (not
shown).
Thus, setting tool 100 of the present invention may be used to axially
displace or
otherwise move, shift, or load a separate wellbore device (not shown), such as
a
fracturing ("frac") plug, packer, swage, bridge plug, or the like.
[0049] Referring to FIGS. 6A and 6B, a power charge is beneficially loaded
into
central bore 18 of pressure sub 10 which is configured to define a pressure
chamber.
Setting tool 100 can be operationally connected to a conventional bottom hole
assembly of a wireline (such as, for example, a wireline bottom hole assembly
that
would be used with a "Baker 20" or other conventional setting tool), typically
via upper
threads 12 of pressure sub 10. Said setting tool 100 can also be connected at
its distal
end to a plug, packer or other tool to be set downhole within a wellbore using
threads
92 of tension mandrel adapter 90 and threads 42 of lower sleeve 40.
Thereafter,
14
CA 3081120 2020-05-14
setting tool 100 of the present invention 10 and the attached device to be
anchored
within a wellbore are conveyed to a desired depth within said wellbore.
[0050] After the aforementioned assembly has been positioned at a desired
setting
depth within a wellbore, said power charge disposed within bore 18 (also
sometimes
referred to as a power charge chamber) is selectively ignited, typically by
some
actuation signal or other triggering action initiated at the surface and
conveyed
downhole to setting tool 100. As said charge burns, gas is generated and
expands
within said pressure chamber formed by bore 18. The design and manufacture of
suitable power charges and their operation within setting tools of the type
described
herein is understood by those in the art and, for clarity and conciseness, is
described
further. It is to be observed that said power charges may be commercially
available,
or specifically designed and manufactured for use in connection with setting
tool 100
of the present invention.
[0051] FIG. 7A depicts a first (upper) portion of setting tool apparatus
100 of the
present invention along line 7-7 of FIG. 5, while FIG. 7B depicts a second
(lower)
portion of said setting tool apparatus 100 of the present invention along line
7-7 of FIG.
5. FIG. 9 depicts a detailed view of the highlighted area depicted in FIG. 7A.
In
operation, setting tool 100 may be used to actuate and set a separate well
tool (not
shown) using a translating assembly well known to those in the art.
[0052] In a preferred embodiment, a force dampening assembly is
beneficially
disposed between said pressure chamber. Said force dampening assembly can
comprise an internal plug 50 having a central aperture 51 and defining an
inner space
CA 3081120 2020-05-14
52. Ball 29, as well as dampening media, is disposed within said inner space
52
formed by said internal plug 50. In the "running" or pre-stroke configuration,
ball 29 is
seated against and obstructs aperture 51.
[0053] Fluid pressure generated within said pressure chamber (bore 18)
exerts
force on ball 29, causing said ball 29 to become unseated from the seat formed
by
aperture 51 of internal plug 50. Said fluid (gas) pressure then forces
dampening media
disposed within inner chamber 52 of internal plug 50 through at least one flow
path 74
(such as an elongate groove or flow channel) extending through threads 73 of
connection member 72. (Said flow channels are not visible in FIGS. 7A and 7B,
but
can be seen in FIG. 3). Said flow path(s) 74 are designed to slow the
expansion of
gas in order to set the downhole tools more smoothly and evenly.
[0054] Unlike conventional setting tools which typically comprise some form
of flow
ports or holes in said pressure chamber (that can become easily clogged or
plugged),
in a preferred embodiment said optimized flow paths 74 may comprise grooves or
channels. Said optimized flow areas permit fluid to flow past said connection
member
72 and tension mandrel 70 in a controlled rate. Although other materials can
be used
without departing from the scope of the present invention, said dampening
media can
comprise a high viscosity material such as grease or other flowable fluid that
has a
desired resistance to flow.
[0055] After a predetermined volume of dampening media has passed through said
optimized flow paths 74, said dampening media then applies pressure to the
piston
area defined by surface 34 of sleeve member 30. A first set of sealing members
16
CA 3081120 2020-05-14
comprises elastomeric sealing elements (0-rings) 60 that engage against inner
surface
31a of central bore 31 of upper sleeve member 30 in order to form a fluid
pressure
seal. A second set of sealing members comprises elastomeric sealing elements
(0-
rings 61) that extend around body section 71 of tension mandrel 70; in the un-
stroked
position (shown in FIGS. 6A and 6B), said 0-rings 61 engage against outer
surface 76
of central mandrel 70 in order to form a fluid pressure seal. However, it is
to be
observed that said 0-rings 61 only engage and form said seal against the
portion of
tension mandrel 70 having the larger outer diameter, but not the (lower)
portion of said
mandrel 70 having the smaller outer diameter; hence no such fluid pressure
seal is
formed by 0-rings 61 in the fully stroked configuration depicted in FIGS 7A
and 7B.
[0056] As the power charge gas further expands, the force generated by fluid
pressure acting on piston surface 34 causes said at least one shear screw 25
to
separate, thereby releasing the locking engagement of said shear screw 25
against
shoulder 17a of radial extension 17 and allowing downward movement of upper
sleeve
member 30 and attached lower sleeve member 40. Such downward movement starts
the setting process of the downhole tool by forcing the outer components
downward
while the inner components remain stationary.
[0057] After tension mandrel adapter 90 enters bore 41 of the lower pressure
sleeve
member 40, the fluid bypass area (that is, the flow path formed by the annular
space
between the outer surface of the mandrel adapter 90 and the inner surface of
bore 41
of lower sleeve member 40 is greatly reduced which acts as a mechanism to
further
regulate the setting stroke. As the power charge burns completely, the setting
tool will
17
CA 3081120 2020-05-14
reach its maximum stroke length; at this point, the downhole tool is
completely set and
released from setting tool 100. Cushion 91 absorbs impact force between lower
surface
33 of upper sleeve member 30 and tension mandrel adapter 90, preventing damage
from repeated impacts from multiple setting iterations. Outer components
(upper
sleeve member 30 and lower sleeve member 40 are then free to stroke completely
and
reach a bleed off position.
[0058] After the stroke of setting tool 100 is complete, seals 60 reach the
top of the
upper pressure sleeve 30 which causes them to come off seat and allow the
remaining
gas pressure to bleed off. Also, seals 61 are permitted to reach the bottom of
the
tension mandrel 70; because the lower portion of said mandrel 70 has a smaller
outer
diameter than the upper portion of said mandrel 70, 0-rings 61 no longer
engage
against said outer surface 76 of mandrel 70 (or form a fluid pressure seal) in
said
stroked portion. As a result, the fluid pressure seal formed by said 0-rings
61 is
released, thereby permitting any remaining fluid pressure to bleed off. Put
another
way, when setting tool 100 is in the fully stroked position, both sets of
integral 0-rings
60 and 61 are unseated, which guarantees bleed off of any internal pressure
downhole.
Furthermore, when setting tool 100 is in the fully stroked position, said 0-
rings 60 are
all visible, thereby allowing users have positive visual confirmation that
setting tool 100
has been fully stroked from a safe distance.
[0059] Setting tool 100 can then be retrieved from a wellbore and can be
redressed
to be run again. In a preferred embodiment, it is to be observed that the
dampening
assembly of the present invention (typically comprising internal plug 50, ball
29 and
18
CA 3081120 2020-05-14
., ..
dampening media such as grease or other highly viscous fluid) can be
separately
removed from setting tool 100 of the present invention, and replaced as a
separate
modular and pre-loaded component to facilitate quick, efficient and cost
effective
redressing of setting tool 100.
[0060] Setting tool 100 of the present invention greatly reduces the
chances of
unintended or inadvertent pre-setting. Shear screw(s) 25 are sized so that
pulling on
setting tool 100 with wireline cannot stroke the tool. A conventional wireline
rope
socket is weaker than said shear screw 25 or the sum of said shear screws'
shear
value; if setting tool 100 becomes stuck within a wellbore, the rope socket
(weak point)
will separate before setting tool 100 will stroke.
[0061] Additionally, the piston area of setting tool 100 is designed
so that said
setting tool will flood with wellbore fluids in the event of a catastrophic 0-
ring leak. Any
pressure downhole would be balanced across the piston area, meaning that
wellbore
pressure cannot inadvertently stroke setting tool 100 (unlike conventional
setting tools
which can inadvertently stroke and if wellbore pressure enters the tool above
the
pistons).
[0062] Top and bottom connections of setting tool 100 are designed to
plug directly
into industry standard wireline equipment (i.e. firing head and wireline
adapter kits for
plugs). The structure, attachment, and use of both the firing head and the
setting
adapter (which are commercially available) is understood by those in the art
and, for
clarity and conciseness, is not described in detail in this disclosure.
Setting tool 100 is
19
CA 3081120 2020-05-14
., .
more rigid than conventional setting tools in order to make the setting tool
of the
present invention less susceptible to bending when running into deviated
wellbores.
[0063] Windows or apertures 44 in the lower pressure sleeve 40 allow easy
access
to wireline adapter kit set screws when the setting tool 100 is in the stroked
position,
thereby expediting the teardown process. Ports in the tension mandrel adapter
allow
wellbore pressure to enter the orifice above a ball on seat which helps to
keep the ball
in place upon release from the frac plug. Conventional tools without this
feature tend
to "suck" the ball off seat when the tool releases.
[0064] The above-described invention has a number of particular
features that
should preferably be employed in combination, although each is useful
separately
without departure from the scope of the invention. While the preferred
embodiment of
the present invention is shown and described herein, it will be understood
that the
invention may be embodied otherwise than herein specifically illustrated or
described,
and that certain changes in form and arrangement of parts and the specific
manner of
practicing the invention may be made within the underlying idea or principles
of the
invention.
CA 3081120 2020-05-14
